Vinyl mercaptobenzazoles [thiazole (VMBT), oxazole (VMBO), and imidazole (VMBI)] were prepared through dehydrochlorination of the respective β-chloroethyl mercaptobenzazoles. These monomers were found to undergo vinyl polymerization in the presence of light or radical initiator, α,α'-azobisisobutyonitrile, to give relatively high molecular weight homopolymers. From the results of radical copolymerizations of these monomers with various monomers, the copolymerization parameters were determined as follows: VMBT(M2): r1styrene(M1): r1= 2.12 ± 0.09, r2= 0.336 ± 0.028, Q2= 0.75, ez= −1.38; VMBO(M2)-styrene(M1): r1= 2.61 ± 0.13, r2= 0.274 ± 0.03, Q2= 0.61, e2= −1.38; VBMI(M2)-styrene(M1) r1=4.0, r2= 0.2, Q2= 0.37, e2= −1.17. The polymerization reactivities of these monomers obtained from these parameters were compared with those of other vinyl sulfide monomers and discussed.